1. Technical Field
The present technology relates to a pneumatic tire, and particularly relates to a pneumatic tire having a tread surface with a cross-sectional configuration that is formed by a plurality of arcs.
2. Related Art
In recent years, advances in reducing the weight of vehicles have been made, and, in the future, problems with vehicle deviation when braking and driving are expected. Vehicle deviation includes phenomena such as lateral drift of the vehicle when braking in order to stop a vehicle that is traveling, and lateral drift of the vehicle when accelerating in order to start a vehicle that is stopped.
For example, in a front engine/front drive type (FF-type) vehicle, a load on the rear wheels is greatly reduced when braking. However, if the center of gravity of the vehicle does not line up with the center of the vehicle, there is a possibility that a moment will be generated in the vehicle and vehicle deviation will occur. In the case of compact vehicles, vehicle deviation is seen prominently when the load on some of the tires is less than or equal to 1 kN.
It is known that the steering stability of a vehicle can be enhanced by sufficiently generating cornering power in such cases as when the load on a part of the tires is greatly reduced. For example, in Japanese Patent No. 4076569 and Japanese Patent No. 4420098, pneumatic tires are described that increase cornering power and particularly enhance steering stability when under light-load conditions by increasing the contact area when under light-load conditions through providing a profile of a tread surface with a flattened form.
With the technology described in Japanese Patent No. 4076569 and Japanese Patent No. 4420098, the performance factor that is enhanced when a tire is under light-load conditions is the steering stability. Moreover, a load on a tire that is considered as a light-load is a load of about 2 kN. Thus, means for generating cornering power under even lighter load conditions (when the load on the tire is 1 kN or less) are not considered. Today, vehicles are getting smaller, and there is a demand for a means for generating sufficient cornering power when under light-load conditions of 1 kN or less.
In light of the foregoing, an object of the present technology is to provide a pneumatic tire that can sufficiently generate cornering power when under light-load conditions and suppress vehicle deviation.